Thus, this invention relates to a process for selection of occupied network resources which must be released to enable higher priority calls in a cellular land mobile system, for example according to the GERAN, UTRAN, E-UTRAN, cdma2000, UMB, WiMAX, etc. standard. These scenarios ordinarily occur in an overload situation.
Occupied network resources must always be released when the available free network resources are no longer sufficient to enable new higher priority calls. Higher priority calls are for example voice calls or streaming calls which are generally called real time applications or real time services. In contrast to real time services, lower priority calls are called non real time service. They include especially applications such as Internet browsing or sending/receiving E-mail.
The prior art in the selection of resources to be released takes into account only resources which are being occupied by individual users. In current land mobile system however resources are also used by several applications or users at the same time, so-called shared resources. A prominent example of a shared resource is the baseband resource of a node B which is being used for HSDPA channels. HSDPA in the node B baseband occupies a certain resource according to the maximum HSDPA bandwidth. The number of users who are sharing the bandwidth is independent of the occupied resources.